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1.
The compatibility of olive barb, Puntius sarana (Hamilton) with major carps was studied in grow-out carp polyculture system for one year in a set of nine earthen ponds of 0.08 ha each. Three different species combinations evaluated were Control: catla (Catla catla Ham.), silver carp (Hypophthalmichthys molitrix Valenciennes), rohu (Labeo rohita Hamilton) and mrigal (Cirrhinus mrigala Hamilton) at 0.5:0.5:1:1; T1: catla, silver carp, rohu and olive barb at 0.5:0.5:1:1 and T2: catla, silver carp, mrigal and olive barb at 0.5:0.5:1:1 at combined density of 7500 fingerlings/ha. While survival levels of the carps did not differ significantly in treatments (P > 0.05), silver carp recorded highest survival levels (94–96%) followed by olive barb (87–90%), mrigal (72–74%), rohu (72–73%) and catla (67–69%). The specific growth rate (SGR) and average harvested body weight (ABW) of catla and silver carp did not differ significantly among the treatments revealing their competition with mrigal or olive barb to be minimum. In absence of rohu in T2, both mrigal and olive barb showed higher SGR and ABW revealing minimal competition between these two species, while their lower performance in presence of rohu in Control and T1 indicated inter-specific competition with the latter. Such olive barb–rohu inter-specific competition, however, failed to yield significant effect on growth of rohu as revealed from its non-significant SGR difference in presence and absence of olive barb. The lower FCR (2.54 ± 0.06) and higher treatment biomass production (3418.4 ± 95.0 kg ha− 1 year− 1) in T1 with rohu–olive barb combination compared to T2 with mrigal–olive barb (2.84 ± 0.11; 3155.1 ± 104.7 kg ha− 1 year− 1) indicated feasibility and advantage of culturing rohu with olive barb rather than mrigal in carp polyculture. Further, similar biomass production in Control and T1 also indicated feasibility of replacing mrigal with olive barb in the grow-out carp polyculture system.  相似文献   

2.
This study was carried out to evaluate the use of commercial live bakers’ yeast, Saccharomyces cerevisiae as a growth and immunity promoter for Nile tilapia, Oreochromis niloticus (L.). Fish (0.33 g) were randomly distributed at 25 fish per 140-L aquarium and fed a diet containing 0.0, 0.25, 0.50, 1.0, 2.0, or 5.0 g yeast/kg diet for 12 weeks. After the 12-week experimental period, fish of each treatment were challenged by pathogenic Aeromonas hydrophila, which was given by interperitoneal (IP) injection and kept under observation for 10 days to record clinical signs and the daily mortality rate. The growth-promoting influences of bakers’ yeast were observed with fish and the optimum growth, feed utilization, and protein turn-over were obtained with 1.0–5.0 g yeast/kg diet. Also, yeast supplementation increased protein deposition in fish body. Biochemical parameters were improved in fish fed yeast up to 1.0 g/kg diet. Total fish mortality 10-days after IP injection with A. hydrophila and its count after incubation with fish serum decreased with the increase of yeast level in fish diets. However, the lowest fish mortality and bacterial counts were obtained in fish fed 5.0 g yeast/kg. These results indicate that bakers’ yeast supplement is promising as an alternative method to antibiotics for disease prevention in tilapia aquaculture, and the optimum level of live bakers’ yeast is about 1.0 g per kg diet.  相似文献   

3.
胡凯  李双安  冯琳  姜维丹  吴培  刘杨  姜俊  邝声耀  唐凌  周小秋 《水产学报》2019,43(10):2256-2267
本实验探索了肌醇对嗜水气单胞菌致生长期草鱼头肾和脾脏氧化损伤的保护作用。实验选取平均体质量（221.83±0.84） g的草鱼540尾,随机分为6组,每组3个重复,分别饲喂含不同水平肌醇[27.0（基础饲料组,未添加肌醇）、137.9、286.8、438.6、587.7和737.3 mg/kg]的饲料10周。随后经腹腔注射嗜水气单胞菌进行14 d攻毒实验。结果显示,嗜水气单胞菌注射后,与基础饲料（未添加肌醇）组相比,饲料中适宜水平肌醇组生长期草鱼头肾和脾脏活性氧（ROS）、丙二醛（MDA）和蛋白质羰基（PC）含量显著降低,而超氧化物歧化酶（SOD/CuZn-SOD和MnSOD）、过氧化氢酶（CAT）、谷胱甘肽过氧化物酶（GPx/GPx1a、GPx1b、GPx4a和GPx4b）、谷胱甘肽S-转移酶（GST/GSTP1、GSTP2、GSTO1和GSTO2）和谷胱甘肽还原酶（GR）活性及mRNA水平,谷胱甘肽（GSH）含量显著提高。此外,饲料中适宜水平肌醇上调了嗜水气单胞菌注射后生长期草鱼头肾和脾脏核因子E2相关因子2（Nrf2）mRNA和蛋白水平,下调了Kelch样环氧氯丙烷相关蛋白1（Keap1）a和b mRNA水平。研究表明,饲料中适宜水平肌醇可激活鱼类头肾和脾脏Nrf2信号途径,提高其抗氧化能力,增强抵抗嗜水气单胞菌致头肾和脾脏氧化损伤的能力。此外,以嗜水气单胞菌注射后生长期草鱼头肾和脾脏ROS含量为标识,生长期草鱼肌醇需要量分别为452.1和449.0 mg/kg。  相似文献   

4.
Atlantic salmon (Salmo salar) brood stock were taken from 32 strains in Norway for 3 consecutive years. Each year, after fertilization, the offspring in each family from each strain were reared in separate egg trays and fingerling tanks. Individual weights and lengths were recorded on a sample of fish from each tank. Environmental and genetic factors influencing the growth rate were studied. The length and weight at a standardized age were significantly affected by hatching date and number of fish held in a tank. There was also a significant ‘tank effect’ which influenced the heritabilities estimated. Significant differences between strains were found for all three year-classes (P<0.01). The estimates of heritabilities found for different year-classes are very consistent. When ‘tank effect’ was removed the heritabilities estimated from the total material were 0.08 for weight and 0.12 for length calculated from the sire components of variance. Calculated from the dam components, the heritabilities were 0.15 for weight and 0.17 for length. The genetic correlation between length and weight estimated from the total material was 1.00. For the ‘trait’ condition factor there were no significant sire and dam components of variance when tank effect was removed.  相似文献   

5.
引起混养塘中异育银鲫和鲢发病死亡的病原及组织病理   总被引：1，自引：1，他引：0  
混养的异育银鲫和鲢鱼种大批死亡,为明确发病死亡的病原和组织损伤并提供相关的疾病防控措施,进行了病鱼肉眼和显微镜检查、细菌学检测、病毒学检测、组织病理和药敏试验研究。结果发现,除在患病鱼体表偶然发现有少量不会引起充血等症状的杯体虫和车轮虫外,未在体内外发现其他寄生虫和真菌类病原;通过细菌分离、人工回感试验、生理生化特性和16S r RNA基因序列分析,从患病异育银鲫和鲢分离到的致病菌株均为嗜水气单胞菌;根据异育银鲫和鲢病毒性疾病的现状,使用鲤疱疹病毒2型(Cyprinid herpesvirus 2,Cy HV-2)DNA聚合酶基因的特异性引物分别对自然发病的异育银鲫和鲢进行PCR检测,只有异育银鲫检测到Cy HV-2,分别用它们的除菌组织上清液进行人工感染试验,只有异育银鲫出现充血症状和死亡现象;由此得出嗜水气单胞菌是异育银鲫和鲢发病死亡的主要病原,Cy HV-2是异育银鲫混合感染的次要病原。患病鲢与患病异育银鲫呈现出类似的组织病理现象,又有一些各自特有的组织病理表现,单纯细菌感染的鲢轻度病变以细胞颗粒变性为主,坏死细胞以核溶解为主,细菌和病毒混合感染的异育银鲫肝脏轻度病变以细胞滴状玻璃样变的变性为主,坏死组织细胞以核固缩和核碎裂为主,在肾脏和脾脏出现染色质边集于核膜的肿大细胞核,主要组织器官出现从变性到坏死的病理变化过程,最终失去应有的功能而死亡。依据药敏试验结果,建议内服诺氟沙星和氟苯尼考等抗生素防治本病的嗜水气单胞菌感染,混合感染Cy HV-2的异育银鲫可以通过注射Cy HV-2疫苗和生态养殖的方法控制和减少该病毒病感染和发展。  相似文献   

6.
Outdoor microcosm tanks were used to grow the penaeid blue shrimp, Litopenaeus stylirostris, in Brunei Darussalam. The tanks were cylindrical, free standing fiber glass tanks of 1827 L water holding capacity and had a self-cleaning mechanism. In three eight-week feeding trials, juvenile shrimp of 0.9–4.3 g were stocked at a density of 28 shrimp/m2. At the end of each trial, survival rates exceeded 80%. Growth rates ranged from 1.19 to 2.46 g/week. Water quality remained stable and within suitable ranges for L. stylirostris growth in all trials. The tanks had algae and bacterial floc developing within a few days of starting the trials. Fourteen commercial shrimp feeds, each containing more than 40% crude protein, were tested in the trials. In spite of the presence of natural food organisms, significant feed-related differences among treatments were found in each trial. In conclusion, microcosm tanks support excellent growth and survival of L. stylirostris and are appropriate for conducting trials to evaluate feeds for pond growout.  相似文献   

7.
草鱼幼鱼生长性状和肌肉成分的遗传参数估计   总被引：3，自引：2，他引：1  
为了研究草鱼幼鱼阶段生长性状和肌肉成分的遗传改良潜力。随机采集288尾人工繁育的4月龄草鱼幼鱼,基于12对微卫星标记,鉴定出来自16个家系（8个母本,9个父本）的273尾个体,各家系、母本和父本对应子代贡献率存在极显著差异（P<0.01）。对草鱼3个生长性状（体质量、体长和肥满度）和2个肌肉成分指标（粗蛋白含量和粗脂肪含量）比较发现,3个生长性状和粗蛋白含量在家系和母系半同胞间存在显著差异（P<0.05）,而3个生长性状和2个肌肉成分指标在父系半同胞间差异均不显著（P>0.05）。基于动物模型和限制性最大似然法,草鱼4月龄体质量、体长、肥满度、粗蛋白含量和粗脂肪含量的遗传力估值分别为0.34、0.33、0.17、0.17和0.20,其中3个生长性状遗传力估值统计检验显著（P<0.05）。遗传相关分析显示,体质量与体长之间呈极显著的高度正相关（0.82, P<0.01）,肥满度与体质量和2个肌肉成分之间存在显著的正相关（0.17-0.29, P<0.05）。研究表明,草鱼4月龄生长性状具有较高的选育潜力,并可通过体长选择实现对体质量的遗传改良;推测在草鱼生长改良过程中,可能会伴随肥满度和粗脂肪含量的变化,这应当引起重视。  相似文献   

8.
Real and simulated data sets were analysed to estimate the effect of data structure (i.e. the number of dams mated to one sire and the number of tanks per dam) and the model used for analysis on the bias of genetic parameter estimates of the square root of 28‐day body weight (BW28) in Penaeus vannamei. Estimated parameters used were 0.13 for the heritability (h2); 0.16 for the proportion of the variance of the maternal and common environmental effects (c2); 0.15 for the proportion of the tank effect variance (t2) and 0.56 for the proportion of the environmental variance (e2). Total variance for the BW28 was 2.36 mg. Simulated data involved a total of 9000 sires and 1 444 000 offspring. Exclusion of maternal and common environmental effects inflated estimates of heritability both in real and simulated data. Exclusion of tank effects from the model inflated the estimates of heritability in real, but not in simulated data, indicating the presence of non‐random effects affecting individual tanks. We conclude that replication of dams per sire is necessary for obtaining unbiased estimates of heritability. Use of replicated tanks may help in reducing overestimation of heritability if tank and genetic effects are confounded.  相似文献   

9.
抗菌药物的应用能对细菌感染性疾病进行有效地控制和治疗,但水产动物养殖中滥用和误用抗菌药物导致耐药细菌的产生、养殖水环境污染和养殖动物药物残留等一系列问题,应对和解决抗菌药物在水产动物养殖中的滥用问题已经刻不容缓。本研究通过抗菌药物杀菌、组织细菌清除、细菌攻毒、鱼体存活率统计和药物敏感性检测等方法,探究外源L-半胱氨酸添加对氟苯尼考杀菌作用的影响。体外杀菌结果显示,4.00 mmol/LL-半胱氨酸可使20.00～200.00μg/mL氟苯尼考对嗜水气单胞菌的杀菌效率提高1.9～11.1倍,其联合用药的杀菌作用具有剂量和时间依赖效应。组织细菌清除结果显示,相比单独使用氟苯尼考,L-半胱氨酸与氟苯尼考合剂对鱼体肝脏、脾脏和肾脏组织中嗜水气单胞菌的清除能力提高4～16倍。细菌攻毒后,采用注射和口服L-半胱氨酸或/和氟苯尼考进行治疗,结果发现L-半胱氨酸与氟苯尼考合剂可大幅提高黄河鲤对嗜水气单胞菌的抗感染能力。同时,单独添加L-半胱氨酸也能促进组织细菌的清除和鱼体的抗感染能力。细菌MIC测定结果显示,添加1.00～4.00 mmol/L L-半胱氨酸使嗜水气单胞菌对氟苯尼考的敏感性提高2～4倍。由此推测,L-半胱氨酸可能通过增强嗜水气单胞菌对氟苯尼考的敏感性,从而提高抗菌药物对鱼体细菌感染的防治效果。研究表明,L-半胱氨酸作为氟苯尼考的增效剂不仅可提高抗菌药物的防治效果,而且可大幅降低抗菌药物的使用量,对嗜水气单胞菌的防控具有一定的实际应用价值。  相似文献   

10.
Columnaris disease is a major cause of mortality in tilapia hatcheries and commonly occurs during the summer season in Thailand. One way of reducing the problem is by selective breeding for increased disease resistance. The objective of this study was to estimate quantitative genetic parameters for resistance against columnaris in the Chitralada 4 strain of Nile tilapia. Data from 43 full‐sib families (2,580 records) of fry (age = 32 ± 4 days post‐hatch) were used in the analyses. Initially, fry were subjected to bath challenge with Flavobacterium columnare (LD50 concentration = 1.2 × 106 CFU/ml) for 14 days. Disease resistance was defined as the number of days from challenge until death (DD) or as a binary trait (dead/alive) on day 14. Linear animal and sire‐dam models were used for DD, while threshold animal, threshold sire‐dam, binary linear animal and binary linear sire‐dam models were used for binary outcomes. Covariate effect of age, fixed effect of challenge day and random effects of the individual animals or sires and dams were included in the models. Mean survival was 32.4 ± 11.6%, and survival rates of the best and poorest families were 70% and 8%, respectively. The highest estimate of heritability (0.30 ± 0.025) was obtained under the threshold sire‐dam model. Heritability estimates for DD (0.16 ± 0.034 and 0.17 ± 0.046) were comparable to those obtained from the threshold animal (0.15 ± 0.031) and the binary linear (0.14 ± 0.045 and 0.15 ± 0.044) models. The linear animal and sire‐dam models for DD and the threshold sire‐dam models performed equally with similar values of rEBV (0.629, 0.628 and 0.627) and accuracy of selection (0.793, 0.793 and 0.791). This study reveals the potential of selective breeding to increase disease resistance to F. columnare in the studied population of Nile tilapia.  相似文献   

11.
为探索嗜水气单胞菌感染后草鱼肾脏细胞(Ctenopharyngodon idella kidney,CIK)中miR-23a的调控机制,实验通过实时荧光定量PCR(qPCR)测定了嗜水气单胞菌感染CIK细胞后miR-23a的表达量变化,使用RNAhybrid软件预测miR-23a的靶基因并用双萤光素酶报告基因检测系统进...  相似文献   

12.
杜仲对草鱼生长、肌肉品质和胶原蛋白基因表达的影响   总被引：1，自引：1，他引：0  
为研究杜仲对草鱼生长性能、肌肉品质及胶原蛋白基因COL1A1和COL1A2表达的影响,实验采用初始体质量为(215.0±0.4)g的草鱼120尾,随机分为2处理组(每组3重复,每重复20尾鱼),分别饲喂基础饲料(对照组)和添加2%杜仲的实验饲料(杜仲组),养殖时间为8周。结果显示,与对照组相比,添加2%杜仲对草鱼生长性能无显著影响,但能显著增加肌肉、皮肤和肝脏胶原蛋白水平,增加肌肉总必需氨基酸(TEAA)、总氨基酸(TAA)水平。2%杜仲可显著降低草鱼肌肉的冷冻失水率、离心失水率,但对肌纤维密度和肌纤维直径无显著影响。在胶原蛋白基因表达方面,2%杜仲显著增加了第4周、8周时草鱼的肌肉、皮肤和第8周时的肝脏组织COL1A1、COL1A2基因m RNA表达量。研究表明,饲料中添加2%杜仲可改善大规格草鱼的肌肉品质。  相似文献   

13.
Genetic effects on cold‐stress tolerance were assessed for red drum (Sciaenops ocellatus), an economically important sciaenid fish in the southern USA. Thirty‐five families were generated via ‘natural’ spawning of multiple sets of five breeders (three dams × two sires) in individual brood tanks. Offspring from the 35 families were transferred abruptly from an acclimation temperature of ～24 °C to 5.7 °C and maintained subsequently at an average temperature of 6.5 °C. Offspring were assigned a posteriori to individual broodfish (dam and sire) based on genotypes at nuclear‐encoded microsatellites. Heritability of the survival–time probability function was estimated using a proportional hazard approach and an animal‐additive model. The estimated heritability was 0.20 (95% CI: 0.07–0.40), indicating a significant genetic component to acute cold‐stress tolerance in red drum.  相似文献   

14.
为研究溶藻弧菌鞭毛蛋白flaC基因DNA疫苗对红笛鲷的免疫保护作用,实验构建了重组真核表达质粒pcDNA-flaC并将该质粒肌肉注射红笛鲷,采用PCR、RT-PCR、ELISA和攻毒试验等方法检测了该真核表达质粒在红笛鲷组织内的分布、表达和对红笛鲷的免疫保护.PCR结果显示,免疫接种7和28 d,注射点周围肌肉、鳃、肾脏、肝脏和脾脏都存在质粒分布;RT-PCR结果显示,免疫接种后第7天、14天和28天,红笛鲷不同组织内均有目的基因表达.ELISA结果表明,鱼血清内产生了抗FlaC蛋白的抗体,表明DNA疫苗免疫后鱼体表达了目的蛋白,并诱导产生了相应抗体.攻毒实验表明,免疫后的红笛鲷能较好地抵抗致病性溶藻弧菌的感染.结果表明,质粒pcDNA-flaC可能是抵抗溶藻弧菌感染的有效的疫苗候选物.  相似文献   

15.
Galaxias maculatus, the common jollytail, is a native smelt fish with a lacustrine or diadromous life cycle. In Chile, the rearing cycle of this fish includes a freshwater and a marine phase. Several diseases and parasites reported for the freshwater phase could be avoided by rearing the fish in salty or brackish water. Nonetheless, this alternative could result in Caligus rogercresseyi infections. The objective of this study was to evaluate experimentally the capacity of C. rogercresseyi to infect the common jollytail and the effects this parasite may cause to the fish. Prevalence and intensity of experimental C. rogercresseyi infections on G. maculatus were estimated and the effects of this parasitosis on the fish were evaluated on fish survival, weight loss, swimming behavior, and skin damage. Two experiments were carried out with adult fish taken from the Maullín Estuary. Fish were acclimatized to a salinity of 32 ppt and divided into two groups of 20 fish each. The experimental group was infected with copepodid stages of C. rogercresseyi and the other was used as a control. The fish were kept in individual tanks until observing ovigerous female copepods. C. rogercresseyi recognizes G. maculatus as a host under experimental conditions and optimal salinity for the parasite. Results show that under experimental condition copepodid stage can successfully infect the fish, developing to the adult stage, mating, and producing eggs (females). C. rogercresseyi caused alterations in fish behavior, superficial body damage, weight loss, and mortality. Rearing the common jollytail in salty water should take into consideration measures to control these infections as they can damage fish and affect surrounding wild fish populations. There are no records of this parasite in natural common jollytail populations; however, our understanding of the ecological role played by the common jollytail in C. rogercresseyi transmissions among sympatric host species could be greatly improved through further research related to host preferences and epidemiological data for different sympatric host species.  相似文献   

16.
Egg yolk immunoglobulins (IgY) were obtained from laying hens immunized with inactivated Aeromonas hydrophila. The purified IgY was shown to inhibit the growth of A. hydrophila in vitro and the optimum concentration for inhibition of A. hydrophila‐specific IgY was 75 mg mL?1. In a subsequent challenge trial, 100 carp (200~250 g) were assigned to one of ten tanks with ten carp per tank. The fish in one tank were unchallenged whereas the remaining 90 fish were injected intraperitoneally with 100 μL of A. hydrophila at a concentration of 108 cfu mL?1. For the next 21 days, all fish were moved in their respective groups to a clean tank for 20 min day?1. The fish in four tanks (one unchallenged tank and three challenged tanks) received no treatment whereas the fish in the remaining six tanks were immersed in either 0.5 g L?1 aqueous nonspecific IgY (N = 3) or 0.5 g L?1 aqueous specific IgY (N = 3). Haemoglobin concentrations, white and red blood cell numbers as well as the mortality of specific IgY‐treated fish were significantly different from those of the control. These results suggest that passive immunization by immersion with pathogen‐specific IgY may provide a valuable treatment for A. hydrophila infection in carp.  相似文献   

17.
An experiment was conducted to evaluate the rearing performance of different larval stages for optimum growth and survival during fingerling production of Clarias batrachus with an aim to reduce the rearing time of the catfish larvae in a hatchery system. The larvae were reared for 5, 10 and 15 days before stocking them in the nursery tanks. No significant (P < 0.05) difference could be found in length increment at the end of first week of rearing. But the total length was reduced during rest three weeks in five days old larvae compared to that of other two higher age groups. In 5 days old larvae the reduced weight (P < 0.05) was observed during the entire rearing period. However, the specific growth rate (SGR) did not vary among the groups. The survival rate as well as total biomass was decreased while stocking five days old larvae for rearing, compared to that of other two age groups.  相似文献   

18.
为探究miR-462在嗜水气单胞菌感染草鱼肾脏细胞(Ctenopharyngodon idella kideny,CIK)后的调控机制,实验利用荧光定量技术检测了CIK细胞感染嗜水气单胞菌后miR-462表达水平的变化;运用RNAhybrid软件预测miR-462的靶基因,利用双荧光素酶报告基因系统进行确定;此外还分析了miR-462对靶基因下游基因的调控作用。结果显示,在CIK细胞感染嗜水气单胞菌的过程中,miR-462的表达发生显著变化;cx32.2、slc9a3.1和tbk1的表达先降低后升高,与miR-462的表达模式呈负相关。双荧光素酶报告系统显示,miR-462可靶向cx32.2、slc9a3.1和tbk1的3′非编码区抑制其表达,过表达miR-462可以显著抑制cx32.2、slc9a3.1和tbk1的表达。转染miR-462模拟物后,下游slc4a4a、tnfrsf5、cxcl9和cxcl11基因的表达受到抑制。研究表明,miR-462参与调控嗜水气单胞菌感染后草鱼CIK细胞中的免疫应答。cx32.2、slc9a3.1和tbk1被鉴定为miR-462的靶基因。miR-462可通过靶向slc9a3.1和tbk1影响下游基因的功能。  相似文献   

19.
This study investigated the effects of the dietary intake of live yeast Debaryomyces hansenii (CBS 8339) on the immune response of juvenile leopard groupers Mycteroperca rosacea and on their resistance to infection by dinoflagellates Amyloodinium ocellatum.During 4 weeks, juvenile groupers were fed either a diet supplemented with D. hansenii at 106 cfu g− 1 or a control diet. Both groups were then transferred to a system infected with A. ocellatum and maintained in this stressful environment, for one week. Rearing conditions were favorable to the proliferation of the dinoflagellate and, at 7 days post-infection, the cumulative mortality rate of the control group was 89.5%, suggesting that the yeast-enriched diet conferred protection against the parasite. Only fish with yeast-supplemented diet recovered from the A. ocellatum challenge.The immunological response of both groups of fish was evaluated. Samples were collected at weeks 4 (stressed fish) and 7 (recovering fish) to determine the levels of hemoglobin, plasmatic protein, and immunoglobulin M (IgM) as well as the activity of antioxidant enzymes (SOD and CAT). IgM increased significantly (P ≤ 0.05) in the recovering fish, which had all been fed the yeast diet. A significantly increase was also observed in superoxide dismutase activity in juvenile fish fed the yeast diet; however catalase activity was not affected by the dietary yeast supplement. Overall, fish that received the yeast supplement in their diet have an enhanced immune response as compared with their control counterparts. The present results show that a diet supplemented with D. hansenii stimulates the immune system of juvenile M. rosacea thus enhancing their resistance against A. ocellatum.  相似文献   

20.
为探究SPR在锦鲤体色形成中的作用,实验利用RACE技术获得spr cDNA全长序列,并分析其时空表达模式,同时利用Western blot和免疫组织化学方法检测SPR蛋白在皮肤、鳍条和鳞片中的分布和表达情况。结果显示,spr cDNA全长879 bp,包含132 bp和134 bp的5′和3′非编码区,开放阅读框510 bp,编码170个氨基酸残基。氨基酸序列比对和系统进化树分析显示,锦鲤SPR具有保守的adh_short_C2结构域,与金鱼相似性高达97.7%。spr在各组织中均有表达,其中皮肤的表达量最高。spr在锦鲤个体发育的4个阶段表现为先降后升。纯红、纯白及红白3种体色锦鲤皮肤、鳞片和鳍条中spr mRNA和蛋白表达水平基本一致,在纯红锦鲤皮肤中表达量最高,红白锦鲤白色皮肤、鳞片和鳍条的表达量最低。SPR组织定位分析显示,红色锦鲤和白色锦鲤皮肤中均检测到阳性信号,其中红色皮肤阳性信号强度高于白色皮肤。研究表明,spr可能与锦鲤红/黄色素细胞的分化和形成具有一定相关性,参与了锦鲤体色的形成。  相似文献   

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